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Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 1:29 pm
by dirvine96
Its my undersatanding that the design of the Hot Blast is more suited for burning bituminous. The manual that comes with stove talks about bituminous and never mentions anthracite. You have to go to there web-site before US Stove even mention anthracite. I think the company know the stove doesn't burn anthracite well, but won't openly admit it. They try to tell you to do this and do that and non of it seems to work. The fire box is wrong and the flu configuration is all wrong for anthracite. US is correct when they say you can burn anthracite in their stove, but guess what you can burn it in a garbage can to. I guess whats got me so upset about the furnace is the lack of custumer support from US Stove. This tells me they know about hte issues with anthracite and continue to sell it and mislead the consumer. I don't blame that as much as I blame myself for not doing more research before I bought.

On a brighter note. I picked up my new Hitzer 82FA and I'm going to take out the Hot Blast and get the Hitzer going. I 'll take a few pic of the new stove and post them.

Don

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Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 3:15 pm
by LsFarm
KTM has it right, there are many variables to getting a good burning stove or boiler. When burning Anthracite you can just about throw out the coal quality variable. Anthracite is very consistant quality. However with Bituminous, the major factor is fuel quality. Technique makes up for firebox design problems, but unless the firebox is designed for Anthracite coal first and wood/bituminous second, it will always be a compromise.

With all the issues I've had with Bituminous, I'm amazed that the US stove burns bituminous well at all. I basicly copied the firebox design of my old MBW boiler, and later saw a US Stove boiler at a TSC store and was amused to see the same design in the firebox. I wouldn't have been so amused if I had realized at that time what a compromise that desgn is.

I think that the US Stove firebox is good for wood, and for adding a load of bituminous on the wood for an occasional longer burn, but it is not good for a long burn with anthracite.

In order to get anthracite to burn well in my boiler, I had to modify my firebox with the help and suggestions from several forum members. I have finally got it so that I can burn anthracite well with 12 hour burns.

With the un modified firebox, [US Stove type design] I can just barely get 8 hours, and have less control over heat output.

KTM's AHS boiler is designed as an anthracite boiler first, with a few features added to make it burn wood and Bituminous. The US stove is the opposite, a wood stove/boiler first, with few add on features that make burning Anthracite possible but a struggle.

I'm sure you will be much happier with your Hitzer 82FA, it looks like a good unit. Take a good look at hte firebox, and take a photo or two, then post those photos with photos of the US Stove firebox, so we can see the difference.

The US stove is a shallow depth, long and wide firebox with tapered firebrick sides down to a center grate. The Hitzer will have very deep box with vertical or near vertical firebrick sides with a grate covering the entire bottom of the firebox. I'm describing the Hitzer firebox sight-unseen, just based on what a correct anthracite burning firebox looks like.

Greg L

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 5:27 pm
by dirvine96
I'll post some pics later to night or tomorrow. I need some advise with the grates on the new Hitzer. They don't give any burns directions for the cast grates. One or two small wood fires should do it I think.

I should be firing it up in and hour or so.

Thanks Don

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 5:53 pm
by LsFarm
Don I'm not sure what advice you need about the grates. Could you clarify??

Greg L

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 6:01 pm
by coaledsweat
I think he wants to season them. A few small wood fires will do it.

You could use a rosebud or even a plumbers torch if your impatient.

All you really are doing is heating it up and cooling it down about 4 times to normalize the iron casting. You really want to do this before you give your expensive grate the anthracite test. :wink:

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 6:17 pm
by LsFarm
I've never heard of seasoning anything but a new cast iron frying pan. :) :lol: :?

I guess normalizing the internal casting stresses make sense. But don't all of our fireboxes have cast grates?? And none of the other manufacturers say anything about conditioning the grates, or have I just missed this.

Greg.

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Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 6:28 pm
by coaledsweat
You are right, very few manuals recommend seasoning. The ones that don't, obviously sell more grates. :)

Actually the gearheads years ago found that high mileage "gramma" cars that made tons of short trips had engines subjected to thousands of thermal cycles. These engines made more power simply because nothing would move anymore. The bores would stay rounder and all the dimensions would remain the same after machining and racing. The low milage stuff would always have casting shifts screwing up all your hard work.
Today, you can accomplish this by bringing the casting up to about 1100F for several hours, then down to about 800F for 8 hours and then slowly allowing it to cool over about 12-16 hours. One cycle and its stable as a rock.

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 6:32 pm
by dirvine96
Thanks guys. I'll build a few small fire before I put the heat to it.

Don

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 11:37 pm
by dirvine96
Here are the pics of the fire box

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 11:42 pm
by dirvine96
The new Hetzer

Re: US Hot Blast Furnace 1557

Posted: Sat. Jan. 20, 2007 11:48 pm
by dirvine96
The Us Stove Hot Blast coming out and the Hitzer going down

Re: US Hot Blast Furnace 1557

Posted: Sun. Jan. 21, 2007 9:00 am
by coaledsweat
Boy, talk about a tight fit! :shock:

The pictures of the firebox, I hope that's the one you took out. The grates and firebox on that would make anthracite burning a woefully hopeless process. The construction does not look real rugged either, which anthracite requires.

It will make someone happy burning wood though. :P

Re: US Hot Blast Furnace 1557

Posted: Sun. Jan. 21, 2007 10:15 am
by LsFarm
I'm pretty sure that is the new Hitzer firebox, those are Hitzer grates, and the firebrick are brand new.
All the US STove models I've looked at have 45* tapered sides with a single narrow grate down the middle, too narrow, chokes with ash too easy, and the ash hangs on the 45* sides. This is what my firebox does.

I personally think it will burn really well. Coaledsweat, why do you think it won't burn well?? The box is deep, about 16'18" from what I see, and vertical sides, I like it.

The grates with the divider down the middle might occasionally have some ash hang up, but if burning pure anthracite, it will burn to powder.

I am currious about the one firebrick out of line on the right side of the first photo. Is this a chute or something?? or did the firebrick get knocked out of place during the move??

Greg L.

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Re: US Hot Blast Furnace 1557

Posted: Sun. Jan. 21, 2007 10:33 am
by coaledsweat
You may be right, I didn't think the firebox was that deep, I figured around 14" and that should be enough. The grate design is what bugged me, and the firebox doesn't taper.

But I'm a boiler guy. 8)

Re: US Hot Blast Furnace 1557

Posted: Sun. Jan. 21, 2007 10:54 am
by LsFarm
Coaledsweat, I think your assesment of the depth is closer than mine, probably 14" at the side, coal could be heaped or mounded in the middle up a few more inches. But plenty of coal for 12-16 hours

I'm more currious about the one firebrick on the right side of the firebox. And of course, the air passageways in the heat-exchanger. It will be interesting to see how the heat is routed and transfered to the air ducts.

Greg.

Here is what a US STove style firebox looks like: